The import org.hibernate cannot be resolved

antlr-2.7.6.jar
cglib-2.2.jar
commons-collections-3.1.jar
dom4j-1.6.1.jar
hibernate3.jar
hibernate-jpa-2.0-api-1.0.0.Final.jar
javassist-3.12.0.GA.jar
jta-1.1.jar
slf4j-api-1.6.1.jar

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